This invention relates to hay conditioning rolls and, more particularly, to elastomeric intermeshing rolls having an improved surface configuration.
The general construction and operation of hay conditioning machines is well described in U.S. Pat. No. 2,811,819 and U.S. Pat. No. 2,921,426 both issued to S. C. Heth and U.S. Pat. No. 3,672,135 issued to Peacock et al., and will not be repeated herein since the invention claimed in the present application involves a roll the surface configuration for use in the machines of the general type described in these patents. Various types of rolls have been used on crop conditioning machines in the past. Originally, most rolls were metal until rubber rolls were developed. Rolls have been made with many types of surface configurations such as ribs, screws and other types of surface variations in an attempt to better perform the function of crimping and/or crushing hay or other similar crops passing between a pair of such rolls. Many of the prior rubber rib configurations did not provide the proper conditioning of both the hay stalks and leaves that is necessary for uniform drying of the hay. In an attempt to provide more uniform crushing and crimping actions, rolls were developed with intermeshing ribs or lugs. A typical example of such prior art rolls are illustrated in U.S. Pat. No. 3,732,670 to Milliken et al., U.S. Pat. No. 3,488,929 to Hale and U.S. Pat. No. 3,513,645 to Garrett et al. The latter patent illustrates interlocking rubber rolls having circumferentially spaced ribs, the ribs being arranged in a chevron pattern. This type of pattern, wherein the point of meshing varies as the roll rotates due to the helical configuration of the ribs, produces a smoother operation and tends to draw material away from both ends of the rolls towards the center thus eliminating bunching at the ends. However, with this type of roll, certain types of lighter material, such as alfalfa, tend to be carried toward the center of the roll and bunch up due to the chevron configuration. Eventually these materials pass through the rolls in a clump which prevents some of the material from being properly conditioned. Further, with the long helical shape, longer stalk materials can become oriented along the length of the groove and not be properly crimped.
Accordingly, it is an object of the invention described and claimed herein to provide a new and improved conditioner roll configuration wherein the slope of the ribs becomes parallel or nearly so to the axis of the roll when the slope of the ribs is reversing from positive to negative.
It is a further object of the invention to provide the surface configuration wherein the slope of the ribs relative to the axis of the roll is continuously variable.
These and other objects of the invention are specifically met in a hay conditioning roll having an elongated cylindrical elastomeric body having a plurality of equally circumferentially spaced ribs extending across the length of the body portion. The ribs and grooves are oriented in a reversing pattern, preferably sinusoidal, across the length of the rolls such that the absolute value of the slope of the ribs relative to the axis gradually decreases to zero, passes therethrough, and gradually increases upon approaching and passing a reversal of the rib pattern. The sinusoidal configuration further provides a continuously variable slope such that long crops cannot lie along the corner of a groove and pass through the rolls without being conditioned.